The present invention relates to a water heating device. More particularly, the present invention relates to a heavy-duty fast-speed direct heating device which uses steam as its heat source.
Water heating devices using steam as heat resources have two major categories, that is, the direct heating type and the indirect heating type. Indirect water heating devices have many limitations in actual production and application due to their low heat efficiency, low heating speed, large heat exchanger size, as well as their vulnerability to clogging due to incrustation.
Although direct water heating devices have the advantages of higher heat efficiency, higher heating speed, smaller size and no incrustation, they can generate enormous noises and shrewd shocks when the steam comes into contact and mixes with the cold water. Therefore, this type of heating devices are usually used where industrial production requires instant heating of a large amount of water.
FIG. 1 is a cross-sectional view of a conventional heater, which includes a casing 21, a steam inlet 24 on one end of the casing 21, and a water outlet 25 on the other end of the casing 21. A steam pipe 22 is coupled to one end of the casing 21. A water inlet 23 is provided on the wall of the casing 21. Such a conventional heater produces considerable noises during operation due to the lack of silencing and depressurization measures.
The present invention provides a direct heating device having advantages, such as low working noise and shock level, high heat efficiency, fast heating speed, small size, high incrustation resistance, high reliability, low maintenance, long service life, flexible and convenient use, as well as high or super high temperature.
The direct heating device can comprise a main casing. The main casing can have a first end adapted to be coupled with a support structure, such as a monoblock fastening flange. One or more water inlets can be formed in the wall member of the main casing near its first end. One or more water outlets can be provided at the second end of the main casing. A sprinkler head can be provided inside the main casing. The sprinkler head can be in a funnel shape having its large diameter end coupled with the support structure, such as the monoblock fastening flange. A critical nozzle in the shape of a long trumpet can be coupled with the small diameter end of the sprinkler head.
In the direct heating device, the water inlets can be spaced away from the first end of the main casing. For example, the water inlets can be spaced from the first end for a distance of about one fourth of the casing length. Additionally or alternatively, the water inlets can be equally spaced on the wall member of the main casing. The number of the water inlets can range from two to six. Additionally or alternatively, the water outlets can be provided in the wall member near the second end of the main casing. The number of the water outlets can range from two to six.
If desired, a high pressure mixing chamber can be provided between the critical nozzle and the water outlets. The mixing chamber can be a round tube.
Optionally, an elbow portion can be mounted to the support structure, for example, on an opposite side of the monoblock fastening flange.
Additionally or alternatively, the main casing can be a double layer construction and comprise outer and inner wall members forming a silencing and shock-isolation chamber therebetween. One or more water inlets can be formed in the inner wall member. The number of the water inlets in the inner wall member can be up to six.
Additionally or alternatively, a pressure relief damper can be provided in the direct heating device. The pressure relief damper can comprise a tail end coupled with the main casing and a tapered end extending into the main casing.
These and other features and advantages of the present invention will be readily apparent from the following detailed description of the invention, the scope of the invention being set out in the appended claims.